Package substrate and manufacturing method thereof, and oled display device

ABSTRACT

Embodiments of the present invention provide a package substrate and a manufacturing method thereof. The package substrate ( 10 ) comprises a central region ( 10   a ) used for being coated with filler adhesive, and a peripheral region ( 10   b ) used for being coated with sealant. Surface of the peripheral region ( 10   b ) at corners thereof includes concave-convex structures ( 101 ). The present invention further provides an OLED display device comprising the package substrate ( 10 ).

FIELD OF THE INVENTION

The present invention relates to the field of display technology, andparticularly relates to a package substrate and a manufacturing methodthereof, and an OLED display device comprising the package substrate.

BACKGROUND OF THE INVENTION

Due to the advantages of self-illumination, high brightness, fastresponse speed, light weight and thinness, full color and no parallax,organic light emitting display (OLED) devices have been applied indisplay field.

An organic material functional layer in an OLED device is particularlysensitive to water vapor and oxygen. If intrusion of water and oxygenoccurs, it is very likely to cause dark spots in a light-emittingregion, which will result in display fault and affect service life ofthe display device.

With respect to an OLED device formed on a glass substrate, glasspackage is mainly adopted in the prior art. For example, after an OLEDdevice is formed on a base substrate, a package substrate may beprovided on the OLED device to cover the OLED device, and the basesubstrate and the package substrate are bonded together throughwater-resistant sealant applied at edges of the base substrate and thepackage substrate, so as to prevent water vapor and oxygen from damagingthe OLED device.

In a dam & filler process, a peripheral region of a package substrate iscoated with sealant and a central region of the package substrate iscoated with filler adhesive, and then the package substrate and a basesubstrate provided with an OLED device are laminated together and curedso as to finish the package. As shown in FIG. 1, in the process ofapplying the sealant, a sealant line 100 is likely to become thinner ata corner of a package substrate 10, which will lead to easy intrusion ofwater and oxygen and thus influence package effect of the device.

SUMMARY OF THE INVENTION

The embodiments of the present invention provide a package substrate anda manufacturing method thereof, and an OLED display device comprisingthe package substrate, which prevent intrusion of water and oxygen byincreasing a contact area between sealant and the substrate, so as toimprove package effect.

According to one aspect of the present invention, there is provided apackage substrate, comprising a central region used for being coatedwith filler adhesive, and a peripheral region used for being coated withsealant. Surface of the peripheral region at corners thereof includesconcave-convex structures.

The concave-convex structure at the corner may be in an L-like shape.

A groove may be provided at a predetermined position in the peripheralregion of the package substrate. The predetermined position is aposition where the sealant starts to be applied.

A cross section shape of the groove may be hemispherical.

The package substrate may be a glass substrate.

According to another aspect of the present invention, there is providedan OLED display device, comprising a base substrate and the packagesubstrate according to the present invention, and an OLED device locatedtherebetween.

According to another aspect of the present invention, there is provideda manufacturing method of a package substrate, the package substratecomprising a central region used for being coated with filler adhesive,and a peripheral region used for being coated with sealant, wherein, themethod comprises processing corners of the peripheral region to formconcave-convex structures.

Mechanical grinding or chemical etching may be adopted to process thecorners of the peripheral region so as to form the concave-convexstructures.

The method may further comprise forming a groove at a predeterminedposition in the peripheral region of the package substrate. Thepredetermined position is a position where the sealant starts to beapplied.

The groove may be formed by etching the predetermined position on thepackage substrate.

According to the embodiments of the present invention, by providing theconcave-convex structures at the corners of the package substrate,frosted surfaces are formed at the corners of the package substrate, sothat a contact area between the sealant and the package substrate can beeffectively increased after the package substrate and the base substrateare laminated together, and intrusion of water and oxygen is prevented,thereby improving package effect of the OLED device.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to illustrate the technical solutions of embodiments of thepresent invention more clearly, the embodiments of the present inventionwill be further described in detail below with reference to theaccompanying drawings. It should be understood that the followingdescription is provided merely for the purpose of illustrating theembodiments of the present invention, rather than limiting the scope ofthe present invention. Those of ordinary skill in the art can makevarious variations and improvements to the embodiments without departingfrom the scope of the present invention. In the drawings:

FIG. 1 is a schematic diagram illustrating distribution of a sealantline at a corner of a package substrate in the prior art;

FIG. 2 is a schematic structural diagram of a package substrateaccording to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a package substrateaccording to another embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a package substrateaccording to another embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a package substrateaccording to another embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a process of applying sealantaccording to the embodiments of the present invention;

FIGS. 7A to 7C are schematic diagrams illustrating various cross sectionshapes of a groove in a peripheral region of the package substrateaccording to the embodiments of the present invention;

FIG. 8 is a schematic diagram of an OLED display device according to theembodiments of the present invention; and

FIG. 9 is an effect diagram of a frosting process on a package substrateaccording to the embodiments of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present invention will be described clearly andcompletely below with reference to the accompanying drawings. However,the described embodiments are just for illustration, but not intended tolimit the scope of the present invention.

FIGS. 2-4 are schematic structural diagrams of package substratesaccording to the embodiments of the present invention.

With reference to FIGS. 2-4, a package substrate 10 according to theembodiments of the present invention comprises a central region 10 aused for being coated with filler adhesive, and a peripheral region 10 bused for being coated with sealant. Surface of the peripheral region 10b at each corner thereof includes a concave-convex structure 101.

The package substrate 10 can be used for packaging an OLED device.According to different light exiting directions of OLED devices, thepackage substrate 10 may be a transparent substrate (e.g. a glasssubstrate) or an opaque substrate (e.g. a metal substrate).

In a process of coating the peripheral region 10 b of the packagesubstrate 10 with the sealant, sealant lines usually become too thin atcorners of the package substrate 10, which will result in decreasedcapability of blocking water and oxygen at the corners. In theembodiments of the present invention, by providing the concave-convexstructures 101 at the corners, frosted surfaces with certain roughnessare formed so as to effectively increase a contact area between thesealant and the package substrate 10, thereby enhancing the capabilityof blocking water and oxygen.

The concave-convex structures 101 are used for forming the frostedsurfaces with certain roughness, and a shape of the region where thefrosted surface is formed is not limited in the present invention, andmay be any one of an L-like shape (as shown in FIG. 2), a T-like shape(as shown in FIG. 3) and an arc shape (as shown in FIG. 4), or any otherirregular shape.

By providing the concave-convex structures 101 on the surface of thepackage substrate 10 at the corners thereof, the frosted surfaces can beformed by the concave-convex structures 101, so that a contact areabetween the sealant and the package substrate 10 can be effectivelyincreased after the package substrate and a base substrate are laminatedtogether, and intrusion of water and oxygen is prevented, therebyimproving package effect of an OLED device.

As shown in FIG. 2, the concave-convex structure 101 at the corner maybe in an L-like shape, that is, the shape of the frosted surface formedby the concave-convex structure 101 may be an L-like shape.

In general, the package substrate 10 is a rectangular substrate. Byproviding an L-shaped frosted surface at each corner of the rectangularsubstrate, it can be ensured that a track of applying the sealant isconsistent with the shape of the frosted surface in the process ofapplying the sealant, so that a contact area between the sealant and thepackage substrate 10 can be effectively increased after the lamination.

In addition, the shape of the frosted surface formed by theconcave-convex structure 101 may be other shape, and is not particularlylimited in the present invention.

FIG. 5 is a schematic structural diagram of a package substrateaccording to another embodiment of the present invention, and FIG. 6 isa schematic diagram illustrating a process of applying sealant accordingto the embodiments of the present invention.

As shown in FIG. 5, a groove 102 is provided at a predetermined positionin the peripheral region 10 b of the package substrate 10. Thepredetermined position is a position where the sealant starts to beapplied.

As shown in FIG. 6, because overflow of the sealant usually happens atthe position where the sealant starts to be applied due to instabilityof equipment, the sealant line is very likely to become too wide afterthe lamination. The entire structure of an electronic device will beadversely affected if the sealant spreads into surrounding circuitregions.

By forming the groove 102 at the position where the sealant starts to beapplied, a storage space for excessive sealant can be provided, so as toavoid too wide sealant line resulting from overflow of sealant, therebyreducing the effect on circuits of the device.

The groove 102 is provided on the track of applying the sealant, and maybe specifically provided in the region where the frosted surface isformed or in the region where no frosted surface is formed on thepackage substrate 10. Because the frosted surface is formed by theconcave-convex structure 101, the structure and shape of the frostedsurface may be affected to a certain extent if the groove 102 isprovided in the region where the frosted surface is formed. As a result,the groove 102 is preferably provided in the region without frostedsurface on the track of applying the sealant.

FIGS. 7A to 7C are schematic diagrams of various cross section shapes ofthe groove in the peripheral region of the package substrate accordingto the embodiments of the present invention.

As shown in FIGS. 7A to 7C, the cross section shape of the groove 102may be a hemispherical shape, a shape of truncated pyramid, acylindrical shape, or any other irregular shape.

The groove 102 is mainly used for accommodating excessive sealantapplied during initial coating, and a drop of the sealant is in anapproximately spherical shape, so the groove 102 having a hemisphericalcross section shape can match the shape of the drop of the sealant best,which will facilitate spreading of the drop of the sealant in the groove102 and also avoid forming bubbles. Therefore, the cross section shapeof the groove 102 is preferably hemispherical.

According to the embodiments of the present invention, the packagesubstrate 10 may be any one of a glass substrate, a sapphire substrate,a silicon substrate and a metal substrate. Whether the package substrate10 needs to be light-transmissive or not can be determined according toa light exiting direction of an OLED device.

FIG. 8 is a schematic diagram of an OLED display device according to theembodiments of the present invention.

As shown in FIG. 8, an OLED display device according to the embodimentsof the present invention comprises a base substrate 20, a packagesubstrate 10, and an OLED device 30 located therebetween. The OLEDdevice may comprise an anode, a cathode, and an organic materialfunctional layer located therebetween.

The base substrate 20 and the package substrate 10 each may be any oneof a glass substrate, a sapphire substrate, a silicon substrate and ametal substrate. Whether the package substrate 10 or the base substrate20 needs to be light-transmissive or not can be determined according toa light exiting direction of the OLED device.

When the package substrate 10 according to the embodiments of thepresent invention is used to package the OLED device 30 formed on thebase substrate 20, a peripheral region 10 b of the package substrate 10may be coated with sealant and a central region 10 a of the packagesubstrate 10 may be coated with filler adhesive, and then the packagesubstrate 10 and the base substrate 20 are laminated together and cured.

A groove 102 is provided at a predetermined position of the packagesubstrate 10, so that a certain storage space for excessive sealantformed during the initial coating can be provided, which avoids too widesealant line after the lamination. In addition, concave-convexstructures 101 are provided at corners of the package substrate 10 toform frosted surfaces at the corners of the package substrate 10, sothat a contact area between the package substrate 10 and the sealant canbe effectively increased after the package substrate 10 and the basesubstrate 20 are laminated together, and intrusion of water and oxygenis prevented, thereby significantly improving package effect of the OLEDdevice and prolonging the service life thereof.

FIG. 9 is an effect diagram of a frosting process on a package substrateaccording to the embodiments of the present invention.

As shown in FIG. 9, a manufacturing method of a package substrateaccording to the embodiments of the present invention comprisesprocessing corners of a peripheral region of a package substrate to formconcave-convex structures 101.

Mechanical grinding or chemical etching may be adopted to process thecorners of the peripheral region of the package substrate so as to formthe concave-convex structures 101.

By taking a case that a glass substrate serves as the package substrateas an example, exemplary description of the processing will be givenbelow. Abrasives such as emery, silica sand and pomegranate powder canbe used to perform mechanical grinding or manual grinding on a surfaceof the glass substrate, so as to form a uniform rough surface.Alternatively, an etching liquid (e.g. hydrofluoric acid) can be used toprocess the glass substrate so as to obtain a frosted surface similar tofrosted glass.

The method of processing the package substrate is not limited thereto,and other methods may be used to process the package substrate accordingto the material thereof, so as to obtain a frosted surface similar tofrosted glass.

The manufacturing method of a package substrate according to theembodiments of the present invention may further comprise forming agroove 102 at a predetermined position in the peripheral region 10 b ofthe package substrate 10. The predetermined position may be a positionwhere the sealant starts to be applied.

The groove 102 may be formed by etching the predetermined position onthe package substrate 10.

An etching liquid matching the material of the package substrate 10 maybe used to etch the package substrate 10.

For example, in the case that the package substrate 10 is a glasssubstrate, hydrofluoric acid can be used to etch the glass substrate soas to form the groove 102. In the case that the package substrate 10 isa metal substrate, dilute sulfuric acid can be used to etch the metalsubstrate so as to form the groove 102.

By forming the groove 102 at the position where the sealant starts to beapplied, a certain storage space for excessive sealant formed initiallycan be provided, so as to avoid too wide sealant line due to theexcessive sealant, thereby reducing the effect on circuits of thedevice.

A cross section shape of the groove 102 is preferably hemispherical. Onthe one hand, the cross section shape of the groove 102 formed by anetching liquid matches the shape of a drop of the etching liquid, so itis relatively easy to form the groove 102 having a hemispherical crosssection shape. On the other hand, the groove 102 having a hemisphericalcross section shape will facilitate spreading of a drop of sealant inthe groove, and also avoid forming bubbles.

The above merely describes the specific implementations of the presentinvention, but the protection scope of the present invention is notlimited thereto. According to the novel teaching of the presentinvention, any person skilled in the art may readily envisage variousvariations and/substitutions, and all of these variationsand/substitutions of the embodiments of the present invention shall beconsidered to fall into the protection scope of the present invention.Therefore, the protection scope of the present invention shall besubject to the protection scope of the claims.

1. A package substrate, comprising a central region used for beingcoated with filler adhesive, and a peripheral region used for beingcoated with sealant, wherein, surface of the peripheral region atcorners of the peripheral region includes concave-convex structures. 2.The package substrate of claim 1, wherein, the concave-convex structureat the corner is in an L-like shape.
 3. The package substrate of claim1, wherein, a groove is provided at a predetermined position in theperipheral region of the package substrate, and the predeterminedposition is a position where the sealant starts to be applied.
 4. Thepackage substrate of claim 3, wherein, a cross section shape of thegroove is hemispherical.
 5. The package substrate of claim 1, wherein,the package substrate is a glass substrate.
 6. An OLED display device,comprising a base substrate, the package substrate according to claim 1,and an OLED device located between the base substrate and the packagesubstrate.
 7. A manufacturing method of a package substrate, the packagesubstrate comprising a central region used for being coated with filleradhesive, and a peripheral region used for being coated with sealant,wherein, the method comprises: processing corners of the peripheralregion to form concave-convex structures.
 8. The method of claim 7,wherein, mechanical grinding or chemical etching is adopted to processthe corners of the peripheral region so as to form the concave-convexstructures.
 9. The method of claim 7, further comprising: forming agroove at a predetermined position in the peripheral region of thepackage substrate, wherein, the predetermined position is a positionwhere the sealant starts to be applied.
 10. The method of claim 9,wherein, the groove is formed by etching the predetermined position onthe package substrate.
 11. The OLED display device of claim 6, wherein,the concave-convex structure at the corner is in an L-like shape. 12.The OLED display device of claim 6, wherein, a groove is provided at apredetermined position in the peripheral region of the packagesubstrate, and the predetermined position is a position where thesealant starts to be applied.
 13. The OLED display device of claim 12,wherein, a cross section shape of the groove is hemispherical.
 14. TheOLED display device of claim 6, wherein, the package substrate is aglass substrate.